The invention relates to beam scanners and the like.
In scanners used for rapidly scanning a beam back and forth along a line, the optical scanning element oscillates about an axis with rotary motion. In order to minimize the driving energy, it is often desired that the scanner be highly resonant, i.e. characterized by a spring-mass system having a high (Q) factor. Certain resonant scanners are severely limited in rotational speed or in the maximum angular excursion that can be obtained. Other scanners are subject to internally induced perturbations that cause detrimental wobbling of the optical element.
In cases where it is desired to employ externally generated drive signals to control a scanner or other rotating oscillator, difficulty and expense are involved in seeking to match the drive signals to the oscillating mechanical system.
The invention is directed to overcoming these difficulties and achieving improved scanning performance and simple and low cost actuator constructions.